/**
 * @param {string[]} nums
 * @return {string}
 */
 var findDifferentBinaryString = function(nums) {
  const n = nums.length
  const arr = nums.map(item => parseInt(item, 2))
  arr.sort((a,b) => a-b)
  if(arr[0] > 0){
    return new Array(n).fill(0).join('')
  }
  for(let i = 1; i<n; i++){
    if(arr[i] - arr[i-1] > 1){
      return (arr[i]-1).toString(2).padStart(n, 0)
    }
  }
  return (arr[n-1]+1).toString(2).padStart(n, 0)
};